Manually lockable seals of this type are known in many variations, for example from Swiss Patent Nos. 481 444, 525 813 and 643 079. They are used to secure locks, where the locking parts in the locking system have openings which, in the locked state of the system, coincide at least approximately, so that the band anchored at one end on or in the seal member can be guided with its other end through the openings. The free end of the band is subsequently guided into the channel of the seal member, where catch members of the band engage the locking members to prevent their withdrawal, so that an opening of the lock sealed in this manner can occur only via destruction of the seal. This security for a lock is desired or demanded in many cases, for example for bag locks, in particular in the case of mail bags, and for the sealing of the loading compartment of vehicles, etc.
These known seals are themselves significantly secured against manipulation in that they can, once closed, no longer be opened without being damaged or altered, and thus permit any manipulation to be recognized. Since, however, we are dealing in the case of such a seal with a pure article of mass production, it is not impossible for malicious persons to obtain open seals of the same type and to exchange an unjustifiably opened seal with a similar new seal in order to cover up the manipulation. Seals permitting this cannot meet high security demands, since with this the purpose of the seal has been avoided. It also does not help that, independently from the seal, documents are often worked out which define the sealed-off goods and permit a check of the goods after the authorized opening of the seal, because these papers can also be easily altered with the copying processes of today.
It is therefore an object of the present invention to improve a seal of the above-mentioned type so that it can be recognized by a clear characteristic as a single piece and therefore, once it has been closed, cannot be exchanged without this being noticed, and which in addition is also essentially protected against other manipulations.